arm64: dts: meson: fix S4 power-controller node

The power-controller module works well by adding its parent
node secure-monitor.

Fixes: 085f7a29 ("arm64: dts: add support for S4 power domain controller")
Signed-off-by: Xianwei Zhao <xianwei.zhao@amlogic.com>
Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>
Link: https://lore.kernel.org/r/20240412-fix-secpwr-s4-v2-1-3802fd936d77@amlogic.comSigned-off-by: Neil Armstrong <neil.armstrong@linaro.org>

arch/arm64/boot/dts/amlogic/meson-s4.dtsi

@@ -65,10 +65,15 @@ xtal: xtal-clk {
 		#clock-cells = <0>;
 	};
 
-	pwrc: power-controller {
-		compatible = "amlogic,meson-s4-pwrc";
-		#power-domain-cells = <1>;
-		status = "okay";
+	firmware {
+		sm: secure-monitor {
+			compatible = "amlogic,meson-gxbb-sm";
+
+			pwrc: power-controller {
+				compatible = "amlogic,meson-s4-pwrc";
+				#power-domain-cells = <1>;
+			};
+		};
 	};
 
 	soc {